The present invention relates in general to a sodium zirconium carbonate compound and the method of its preparation. In particular, the present invention relates to a novel sodium zirconium carbonate compound which, when prepared according to the method of the invention exhibits a substantially uniform particle size.
It is known in the art to make zirconium carbonate compounds by precipitating the compounds from a solution of zirconium sulfate and alkali carbonate at a pH of about 6 to 7 as disclosed in Wainer U.S. Pat. No. 2,316,141 and Brownlee German Pat. No. 2,510,743. Wainer also teaches that at a lower or higher pH, the zirconium compound redissolves. A sodium zirconium carbonate having the empirical formula Na.sub.4 [ZrOZr(OH).sub.2 (CO.sub.3).sub.4 ].8H.sub.2 O is reported by Pospelova and Zaitsev in the Russian Journal of Inorganic Chemistry pp. 995-1004, Vol. II No. 8 (August 1966). The compound is formed by adding zirconium oxychloride solution to hot saturated sodium carbonate and is readily soluble in water.
The sodium zirconium carbonate compound of the present invention can be used in the preparation of zirconium phosphate which is useful as an ion exchanger. In some applications, it is desired to obtain zirconium phosphate particles having a uniform particle size. It is known in the art that the particle size of the zirconium phosphate product can be controlled by controlling the particle size of the zirconium starting material. Therefore, in order to form a zirconium phosphate product which has a uniform particle size range it is desirable to begin with a starting material which has a uniform particle size range.